What about using it on Straight Talk wireless. They sell the cards at Wal-Mart and it says it uses Verizon's Network. So I would think that it would work. I tried calling Straight Talk but I get a recording telling me to call back later.

Straight talk wouldnt work. CDMA phones dont use sim cards. Straight talk uses a ton of different networks, but basically depending on which phone you buy from them determines which phone you use. Like the ones that have sims in them use t-mobile or AT&T's network, and the ones that dont are CDMA phones that use Verizon and Sprints network. And they unfortunately wont activate any phone on their service that isnt bought specifically with Straight Talk branding, and the Sim cards are also locked to Straight talk phones.

Are you talking about the eris? The eris has no sim card, or anything of the sort. It uses a number called an ESN that is built into the phone. To activate it you just go to verizons website and enter in said ESN number, and then its working just as if you put a sim into it. However, Verizon will only activate phones branded verizon wireless that are in their registry. If the phone is reported stolen, it gets deleted from the registry (Hence the term bad esn). Sprint does the same thing. So you couldnt activate a Verizon branded phone on sprint. But there are a few carriers that will activate any phone, such as cricket and metro PCS but you have to do a little bit of work flashing it or theyll do it for you for around $20.